Fixes to Cast use of overlays for video frames

ui/ozone/platform/cast/overlay_manager_cast.cc

Index: ui/ozone/platform/cast/overlay_manager_cast.cc
diff --git a/ui/ozone/platform/cast/overlay_manager_cast.cc b/ui/ozone/platform/cast/overlay_manager_cast.cc
index cb7d6419ba97d83aeacc4b1f1578694c579e1db5..9d173008ce9880bc57e4630adaf02e2b16d34df1 100644
--- a/ui/ozone/platform/cast/overlay_manager_cast.cc
+++ b/ui/ozone/platform/cast/overlay_manager_cast.cc
@@ -4,6 +4,11 @@
 
 #include "ui/ozone/platform/cast/overlay_manager_cast.h"
 
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/memory/ref_counted.h"
+#include "base/single_thread_task_runner.h"
+#include "chromecast/media/base/media_message_loop.h"
 #include "chromecast/public/cast_media_shlib.h"
 #include "chromecast/public/graphics_types.h"
 #include "chromecast/public/video_plane.h"
@@ -13,6 +18,16 @@
 namespace ui {
 namespace {
 
+void SetVideoPlaneGeometry(
+    const chromecast::RectF& display_rect,
+    chromecast::media::VideoPlane::CoordinateType coordinate_type,
+    chromecast::media::VideoPlane::Transform transform) {
+  chromecast::media::VideoPlane* video_plane =
+      chromecast::media::CastMediaShlib::GetVideoPlane();
+  CHECK(video_plane);
+  video_plane->SetGeometry(display_rect, coordinate_type, transform);
+}
+
 // Translates a gfx::OverlayTransform into a VideoPlane::Transform.
 // Could be just a lookup table once we have unit tests for this code
 // to ensure it stays in sync with OverlayTransform.
@@ -37,31 +52,60 @@ chromecast::media::VideoPlane::Transform ConvertTransform(
   }
 }
 
+bool ExactlyEqual(const chromecast::RectF& r1, const chromecast::RectF& r2) {
+  return r1.x == r2.x && r1.y == r2.y && r1.width == r2.width &&
+         r1.height == r2.height;
+}
+
 class OverlayCandidatesCast : public OverlayCandidatesOzone {
  public:
-  void CheckOverlaySupport(OverlaySurfaceCandidateList* surfaces) override {
-    for (auto& candidate : *surfaces) {
-      if (candidate.plane_z_order == -1) {
-        candidate.overlay_handled = true;
-
-        // Compositor requires all overlay rectangles to have integer coords
-        candidate.display_rect = gfx::ToEnclosedRect(candidate.display_rect);
-
-        chromecast::media::VideoPlane* video_plane =
-            chromecast::media::CastMediaShlib::GetVideoPlane();
-
-        chromecast::RectF display_rect(
-            candidate.display_rect.x(), candidate.display_rect.y(),
-            candidate.display_rect.width(), candidate.display_rect.height());
-        video_plane->SetGeometry(
-            display_rect,
-            chromecast::media::VideoPlane::COORDINATE_TYPE_GRAPHICS_PLANE,
-            ConvertTransform(candidate.transform));
-        return;
-      }
+  OverlayCandidatesCast()
+      : media_task_runner_(
+            chromecast::media::MediaMessageLoop::GetTaskRunner()),
+        transform_(gfx::OVERLAY_TRANSFORM_INVALID),
+        display_rect_(0, 0, 0, 0) {}
+
+  void CheckOverlaySupport(OverlaySurfaceCandidateList* surfaces) override;
+
+ private:
+  scoped_refptr<base::SingleThreadTaskRunner> media_task_runner_;
+  gfx::OverlayTransform transform_;
+  chromecast::RectF display_rect_;
+};
+
+void OverlayCandidatesCast::CheckOverlaySupport(
+    OverlaySurfaceCandidateList* surfaces) {
+  for (auto& candidate : *surfaces) {
+    if (candidate.plane_z_order != -1)
+      continue;
+
+    candidate.overlay_handled = true;
+
+    // Compositor requires all overlay rectangles to have integer coords
+    candidate.display_rect = gfx::ToEnclosedRect(candidate.display_rect);
+
+    chromecast::RectF display_rect(
+        candidate.display_rect.x(), candidate.display_rect.y(),
+        candidate.display_rect.width(), candidate.display_rect.height());
+
+    // Update video plane geometry + transform to match compositor quad.
+    // This must be done on media thread - and no point doing if it hasn't
+    // changed.
+    if (candidate.transform != transform_ ||
+        !ExactlyEqual(display_rect, display_rect_)) {
+      transform_ = candidate.transform;
+      display_rect_ = display_rect;
+
+      media_task_runner_->PostTask(
+          FROM_HERE,
+          base::Bind(
+              &SetVideoPlaneGeometry, display_rect,
+              chromecast::media::VideoPlane::COORDINATE_TYPE_GRAPHICS_PLANE,
+              ConvertTransform(candidate.transform)));
     }
+    return;
   }
-};
+}
 
 }  // namespace